Dual chamber vacuum storage and dispenser for coffee beans

Abstract

A system and method for storing coffee beans in a vacuum environment and dispensing them into an external environment at atmospheric pressure is provided. An upper valve selectively passes coffee beans from a hopper to a metering chamber when open and forms an airtight seal between the metering chamber and the hopper when closed. A lower valve selectively dispenses the coffee beans from the metering chamber when open and forms an airtight seal between the metering chamber and the external environment when closed. An actuator mechanism synchronously operates the upper and lower valves to establish and maintain a vacuum environment in the hopper while dispensing an accurate quantity of coffee beans on demand.

We claim: 
     
       1. A system for storing and dispensing flowable food product into an external environment at atmospheric pressure comprising: means including a first chamber for storing the flowable food product;   air-tight seals coupled to the first chamber to isolate the first chamber from the external environment; and   means including a second chamber for removing a quantity of the flowable food product from the means for storing while maintaining the means for storing substantially isolated from the external environment, wherein said second chamber is positioned beneath the means for storing and the means for removing further comprises: a first valve positioned between the means for storing and the second chamber, the first valve sized to allow the coffee beans to pass from the means for storing to the second chamber, wherein the first valve serves as one of the air tight seals to selectively isolate the second chamber from the means for storing; and   a second valve positioned beneath the second chamber, the second valve sized to allow the coffee beans to pass from the second chamber to the external environment, wherein the second valve is air tight to selectively isolate the second chamber from the external environment.     
     
     
       2. The system of claim 1 further comprising a vacuum pump coupled to the second chamber so as to evacuate the second chamber. 
     
     
       3. The system of claim 2 wherein the means for storing is evacuated by opening the first valve while the second chamber is evacuated. 
     
     
       4. The system of claim 1 wherein the first and second valves are configured as ball valves comprising: a housing having a cavity formed therein; and   a spherical ball having a bore through a central axis, the bore sized to allow coffee beans to flow through in a first position and an outer surface of the ball making an airtight seal between the second chamber and the means for storing in a second position.   
     
     
       5. The system of claim 1 further comprising actuator means for controlling the first and second valves such that the first and second valves cannot simultaneously be open. 
     
     
       6. A system for storing and dispensing flowable food product into an external environment at atmospheric pressure comprising: means including a first chamber for storing the flowable food product;   air-tight seals coupled to the first chamber to isolate the first chamber from the external environment; and   means including a second chamber for removing a quantity of the flowable food product from the means for storing while maintaining the means for storing substantially isolated from the external environment, wherein the means for storing is filled with an inert gas.   
     
     
       7. A method for dispensing flowable product from a hopper, particularly roasted coffee beans, the method comprising the steps of: providing an upper valve having an inlet coupled to the hopper and an outlet, the upper valve initially being open;   providing a chamber coupled to the upper valve outlet;   providing a lower valve having an inlet coupled to the chamber and an outlet for dispensing the product, the lower valve initially being closed;   applying a vacuum source to the chamber to evacuate gasses from the chamber;   filling the cheer with the product by flowing the product from the hopper through the upper valve to the chamber;   closing the upper valve;   shutting off the vacuum source to the chamber; and   only after the vacuum is shut off, opening the lower valve to dispense the contents of the chamber through the outlet of the lower valve.   
     
     
       8. The method of claim 7 further comprising the steps of: closing the lower valve after the product is dispensed;   reapplying the vacuum source to the chamber;   opening the upper valve; and   transferring the product from hopper to the chamber.   
     
     
       9. The method of claim 7 further comprising the steps of: after the step of closing the upper valve, bleeding air into the hopper;   opening the hopper;   refilling the hopper;   closing the hopper with an airtight seal;   opening the upper valve, thereby coupling the chamber to the hopper; and   evacuating the hopper using the vacuum source coupled to the chamber.   
     
     
       10. An apparatus for dispensing a predetermined quantity of product from a hopper, the apparatus comprising: a first valve having an inlet coupled to the hopper and having an outlet;   a meter chamber coupled to the outlet of the first valve, the meter chamber having a fixed volume defined by a plurality of inner walls;   a second valve having an inlet coupled to the meter chamber and having an outlet for dispensing the product into an external environment;   an actuator for controlling the first and second valves allowing the first and second valves to be simultaneously closed to isolate the meter chamber from the hopper and isolate the meter chamber from the external environment; and   a removable insert affixed to at least some of the plurality of inner walls for decreasing the volume of the meter chamber.   
     
     
       11. The apparatus of claim 10 wherein the volume displaced by the removable insert is determined by density of the product. 
     
     
       12. The apparatus of claim 10 wherein the first and second valves are non-metering valves. 
     
     
       13. A valve assembly for removing a fixed quantity of flowable product from a pressure isolated storage container, the valve assembly comprising: an upper valve having an opening sized to allow the product to flow through when the upper valve is open, the upper valve making an airtight seal with the storage container when closed;   a meter chamber having an inner surface, the chamber adapted to receive the product from the upper valve;   a removable insert affixed to the inner surface of the meter chamber for reducing volume inside the meter chamber, the size of the removable insert determined by density of the product; and   a lower valve having an opening sized to allow the product to flow through when the lower valve is open, the lower valve making an airtight seal with the meter chamber when closed.   
     
     
       14. The valve assembly of claim 13 further comprising a port located in a wall of the meter chamber for receiving a vacuum line from an external vacuum source. 
     
     
       15. The valve assembly of claim 13 further comprising an actuator means coupled to the upper valve and the lower valve for synchronously operating the upper and lower valves. 
     
     
       16. The valve assembly of claim 15, the actuator means further comprising a vacuum switch, the vacuum switch having an inlet coupled to an external vacuum source and an outlet coupled to the meter chamber. 
     
     
       17. The valve assembly of claim 16 wherein the upper valve includes a cutting surface positioned at a junction between the upper valve and the meter chamber. 
     
     
       18. The valve assembly of claim 17 wherein the lower valve includes a cutting surface positioned at a junction between the lower valve and the meter chamber.